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Discussion Starter #1
The 4 door died...Heres the prob

Has a 351

Drove it to the bar ran fine
left bar ran good
stopped to pick a friend up & the truck killed
had to pump the gas to get it going & ran well till I dropped him off
killed in front of his house
pumped it again it ran perfect till I got it home
died in front of my house & wont start now

The fuel pump powers up & im getting fuel to the fuel rail..
Not getting any spark that I can see
I did replace the coil with a brand new one...

The motor also shakes pretty bad when I spin it over
found out I had the #1 plug wire off & the #2 was almost off but the truck always ran fine..



So any ideas?? Could it be the TFI module??


Thanks for any help...
 

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if you had the plug wires off you prolly fouled those two plugs, and yes, that could have killed the ignition module. a good stiff breeze can kill a tfi. could also be the tps since you had to pump the accelerator...which does exactly nothing on an efi vehicle, except to make the tps move and make a connection. the tps is basically like a rheostat in function, in that where it is in its travel sends a voltage signal to the computer and tells it how much fuel to squirt. if it is sending the wrong / no signal, the computer will not tell the injectors to pulse, and let the fuel flow from the rail to the cylinders. the fact that the engine is shaking badly leads me to believe your timing is off as well...did you put the plug wires back on the correct plugs?
 

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Check the condition of the wires and plugs. Make sure the firing order is correct, and the timing. It may be the TFI, but that is where I would start.
 

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Discussion Starter #6
Changed the TFI & It fires but dosent start... Starts using starter fluid & will then run on its own....What next?? Still fuel pump?
 

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not likely. the fuel pump is (typically) either good or bad. there is *usually* no iffiness to it. it either works or it dont. sounds like maybe the fuel pressure regulator on the fuel rail is letting the residual pressure bleed back out of the rails when it sits. therefore it needs to be primed at each start. caveat...on rare occasion, it has been noted that the fuel pump itself can have a defect which will not allow it to build proper pressure, and it will need to be replaced, even though the pump motor itself is running. when you turn the key to "on", but not try to start, can you hear the pump prime for just a second? does it run for a second then stop? (proper) or keep running? (not good). losing prime can also mean leaky injectors, but its not likely all 8 of them are leaking. check all your fuel lines for leaks, and check the little shraeder valve on the fuel rail (pressure testing valve) to make sure it is sealing. these are both often overlooked little issues that can cause loss of fuel prime.
 

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Discussion Starter #8
not likely. the fuel pump is (typically) either good or bad. there is *usually* no iffiness to it. it either works or it dont. sounds like maybe the fuel pressure regulator on the fuel rail is letting the residual pressure bleed back out of the rails when it sits. therefore it needs to be primed at each start. caveat...on rare occasion, it has been noted that the fuel pump itself can have a defect which will not allow it to build proper pressure, and it will need to be replaced, even though the pump motor itself is running. when you turn the key to "on", but not try to start, can you hear the pump prime for just a second? does it run for a second then stop? (proper) or keep running? (not good). losing prime can also mean leaky injectors, but its not likely all 8 of them are leaking. check all your fuel lines for leaks, and check the little shraeder valve on the fuel rail (pressure testing valve) to make sure it is sealing. these are both often overlooked little issues that can cause loss of fuel prime.
Makes the proper sounds and runs just a second like it should, no visable leakes in any of the fuel system...


Ill do some more checking tomorrow... Might have some help comming..
 

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Discussion Starter #10
i would be leaning towards it being the regulator.
Changed that out with a new one....

New prob... If I cycle the fuel pump a few times it will start/run... When I put it in gear it dies.. Drive & reverse...



Now what could the prob be???? Im trying all the cheap stuff before I spend the big money on a pump....
 

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I wouldn"t expect the fuel pump to be the problem. I would look at the idle air control valve first, like you say you need to pump the gas to get it started, if the IAC isn't opening, pumping the gas may be giving it the air it needs.
 

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Discussion Starter #13
I wouldn"t expect the fuel pump to be the problem. I would look at the idle air control valve first, like you say you need to pump the gas to get it started, if the IAC isn't opening, pumping the gas may be giving it the air it needs.
Not really pumping the gas... cycling the fule pump to build pressure more like
 

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penis
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bad pump clogged fuel filter bad FPR. Go this route change fuel filter, then check vac line for the FPR for the smell of gas then pressure test the fuel system
 

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Discussion Starter #15
bad pump clogged fuel filter bad FPR. Go this route change fuel filter, then check vac line for the FPR for the smell of gas then pressure test the fuel system
New fuel filter,new fuel regulator,no leaks anywhere9 fuel or vacume),new battery...

I get 30 to 40 PSI on the fuel pressure gage running & off....

Took it for a drive & it ran for a few miles & died... Its back to running but killing when I put it in gear...

Tomorrow I think Im going to blow air thru all the fuel lines & make sure they arnt clogged anywhere
 

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penis
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Is it 30 or 40? or sititing in the middle, I would check it while driving see if it drops off. By this I mean go for a drive and watch the fuel pressure gauge see if it drops as you drive. Does it drop when you are driving at a steady speed or when there is a load on the motor, and bucking sensation? when it is cold will it fire right back up? Also have you pulled any codes? The only thing I can think of if it is not a fuel problem is the ignition control module is acting up when it gets hot killing the motor due to it overheating or given a load.
 

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It actually does sound like your fuel pump, I was having the same problems and left my fuel pressure gauge on the fuel rail while driving and watched the fuel pressure drop after a while (mainly when hot and pulling grades), turned out the fuel pump was not able to maintain pressure to feed the rail...

I replaced the FPR but it had no affect.. replaced the fuel filter too.

When I removed the fuel pump the bottom filter pickup was clogged.. put a new pump and filter in the tank and runs great.. maybe pull it and check the filter on the pump if you have one in the tank or replace the pump while your in there.. you can always return it if its not the case...

Anyway I know same symptoms are not always the same problems but maybe it will help you out.
 

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fuel reservoir? Had same issues till it puked. Installed new filter and cleaned the little valves and she was running.

recent fuel res issues, solved
 

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Discussion Starter #19
OK... We have the fuel prob solved... Now the next prob is the ignition switch...

Parts store says theres 3 parts to buy so I have no clue which it is...

With the truck running,shifting into gear it will kill,taping on the steering wheel it will kill...

Could it be the ignition switch or the ignition cylinder???


Im just trying to get an idea before we work on it again tomorrow...
 

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OK... We have the fuel prob solved... Now the next prob is the ignition switch...

Parts store says theres 3 parts to buy so I have no clue which it is...

With the truck running,shifting into gear it will kill,taping on the steering wheel it will kill...

Could it be the ignition switch or the ignition cylinder???


Im just trying to get an idea before we work on it again tomorrow...
Please tell us what fixed your fuel issue. People years down the road can come back to this and may have the same exact problem. I cant count how many year and year old threads that have saved me!

Secondly, what transmission? If its the E4OD, then you really need to check the MLPS, as it may be getting a bad signal.

When your truck starts to run like shit, do you pull a spark plug wire off to see it its a nice strong blue spark?? Do you smell gas when it wont start??
 
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